Capital Mysteries Books in Order

Watching the president on television, K.C. Corcoran notices stiff movements and an unfamiliar signing hand. Convinced something is wrong, she recruits her friend Marshall to investigate whether the president has been replaced by a clone.

K.C. and Marshall attend the Cherry Blossom Festival with President Thornton and K.C.'s mother. While the children get ice cream, the adults are kidnapped, leaving the young investigators determined to help the FBI.

KC and Marshall explore the Smithsonian when a man claims the money used to establish the museum should belong to him. They search for evidence that his claim is false before the institution falls into his hands.

KC's mother is preparing to marry the president, but private wedding details keep appearing in the newspapers. KC and Marshall try to discover who is leaking secrets from the White House before the wedding is spoiled.

The president plans a celebration honoring the sculptor of the Lincoln Memorial statue, but KC and Marshall discover that Lincoln's thumb is missing. They investigate the damaged monument and search for the missing piece before the event.

During Fourth of July festivities, KC sees fireworks coming from the FBI building. While the president assumes it is an accident, she and Marshall suspect the display may have concealed a crime and begin investigating.

KC and Marshall tour the Treasury's printing and engraving building and discover that a bundle containing a hundred thousand dollars has disappeared. They investigate how a thief could remove the money past cameras, guards, and locked doors.

KC and Marshall attend a National Zoo fundraiser featuring a precious jewel loaned to support endangered tigers. When the lights go out and the jewel disappears, they investigate a theft from a room with tightly controlled access.

Camping on the White House lawn, KC and Marshall notice lights flickering high in the Washington Monument. Investigating the strange sight leads them to peanut shells, a broken stone, and a monkey, leaving them to connect the clues.

With the presidential election approaching, doctored photographs appear online after a White House Halloween party. KC and Marshall investigate who is trying to damage President Thornton's reputation and stop the false images from affecting his reelection campaign.

KC and Marshall discover old toy horses belonging to Thomas Jefferson in a White House hiding place. After taking them to Monticello, they find the collection has been stolen and investigate how the thief escaped notice.

KC and Marshall visit Camp David on President Eisenhower's birthday, when legend says his ghost appears. A trapped bat, red dirt, and strange thumping noises make them investigate what is causing the unsettling activity in their cabin.

KC and Marshall ride an express train with the vice president and Secret Service protection. When they leave their special car to explore, someone tampers with the train and begins searching for them through the carriages.

KC and Marshall arrange to save more than the single turkey usually pardoned at Thanksgiving. When all 117 birds disappear from the National Mall overnight, the friends investigate who took the flock before it could be released.